Catalyst-free growth of pyramidal zinc sulfide nanostructure arrays on single walled carbon nanotubes

Uniform and ordered pyramidal zinc sulfide (ZnS) nanostructure arrays have been fabricated on the single walled carbon nanotube (SWNT) films by chemical vapor deposition without using any metal catalyst. Each ZnS pyramid has a 100 nm-sized base, a uniform length of 600 nm, and a sharp tip of 10 nm. The control of interspatial distance between ZnS nanostructures was achieved by creation of selective growth on the SWNTs in voids with the assistance of a close-packed silica particle monolayer as a template. Furthermore, this kind of morphology control of nanostructure arrays can play an important role for potential applications, such as high efficiency of field emission because of the strong correlation between shapes and functionalities of nanostructures.